The average college student graduated with $27,200 in debt (The Boston Globe, May 27, 2012). Let debt among recent college graduates be normally distributed with a standard deviation of $7,000.

a. What is the probability that a recent college graduate has debt of less than $25,000?

b. What is the probability that a recent college graduate has debt of more than $30,000?

c. What is the amount of debt that places a recent college graduate in the bottom 10% in terms of debt?

d. What is the amount of debt that places a recent college graduate in the top 15% in terms of debt?